1.3. Environmental history

The characteristically monotonous nature of Hebridean vegetation, dominated by blanket peat and moorland, is not entirely representative of its character through time. It has long been supposed that the islands were always devoid of substantial tree cover but, more recently, Brayshay and Edwards (1996, 23) proposed that timber cover may have been quite dense within certain areas for most of the early to mid Holocene, and continued re-assessment suggests that woodland may have been managed as a resource into the Iron Age (Harding and Gilmour 2000, 1; Church 2002, 72).

The Holocene in the Western Isles has seen the decline of both timber resources and fertile land through peat initiation and rising sea levels (Armit 1996, 28; Ritchie 1985). However, the parallel growth of blanket peat bog produced a valuable source of fuel and building materials, while the continuous development of machair has provided increased potential for an arable economic component, somewhat offsetting the negative impact of sea level change; a saving grace for islanders has been the widespread development of this coastal machair landscape produced by the natural fertilisation of the black peaty soil by wind-blown shell-rich sand, transforming it to a fertile calcareous soil (Branigan and Foster 2002, 19).

The economy of the islands has tended to be largely pastoral including a long tradition of transhumance, with evidence for shielings from the Neolithic period. Nonetheless, the areas with reasonable land have always included an arable component in their economy, and similarly, the areas with good access and suitable craft have relied on the products of the sea. In the medieval period this arable component centred on the 'runrig' system, where settlement was dynamic and clustered, and each family cultivated furrows in different parts of the communal lands (Dodghson 1993) (Fig. 6). This was replaced in the 18th century by the system of crofting, where the settlement was linear and each family worked a strip of land and had access to communal grazing. Throughout the last millennia, settlement has tended to focus on the west of the islands since the machair is better both for arable production and as grazing. Recent east coast settlement foci such as Castlebay on Barra and Stornoway on Lewis are a product of attempts in the mid-19th century to support a herring industry.

Figure 6: The earliest known photo of the village on Mingulay, taken in
1887 (Buxton 1995, plate 1). This cluster of buildings is more
characteristic of Hebridean settlement prior to crofting. The village, and
the island, were finally abandoned in 1912